ABSTRACT This study reports the preparation and application of a low-cost activated carbon produced from beech wood residues (BW-AC) via phosphoric acid activation. The adsorbent possessed a mesoporous-dominated, amorphous structure with a high specific surface area of 867.3 m2 g−1. The efficacy of BW-AC was evaluated for tetracycline (TC) removal from aqueous solutions. The effects of key operational parameters, including pH, contact time, adsorbent dosage, initial TC concentration, and temperature, were systematically investigated. TC adsorption was largely pH independent, whereas increasing the adsorbent dosage improved TC uptake, with an optimal range of 1–1.5 g L−1. Robust statistical model selection using the corrected Akaike information criterion (AICc) and Bayesian information criterion (BIC) identified the general-order kinetic model as the best fit, with AICc and BIC values of –38.43 and –41.18, respectively. Among the isotherm models, the Langmuir model provided the best representation of equilibrium data, yielding AICc and BIC values of 73.61 and 72.64, respectively, and a maximum adsorption capacity (Qmax) of 219.9 mg g−1 at 20 °C. Thermodynamic analysis confirmed a spontaneous, endothermic, and entropy-driven adsorption process. These findings collectively demonstrate that BW-AC is an efficient, sustainable, and cost-effective adsorbent for the removal of TC from contaminated water.
Asgharnia et al. (2026) studied this question.